1. Field of the Invention
The invention relates to a device for automatic control of the storage capacity put to work in automatic data processing systems or data transmission systems.
2. Description of the Prior Art
In data processing or data transmission systems the memories or stores store a more or less extensive volume of data. The extent of this volume of storage of data is referred to as the "Storage Capacity" of the system. The data contained in this volume is all registered by an address. Hence this volume contains a start address and an end address or storage capacity limit address. For obvious economic and commercial reasons the stores are cut up into modular elements. These storage elements or modules form pieces of the total storage and individually represent a small capacity. Hence their cost is much lower than a complete store.
At the start of its operation, a system may be operated with a store of small capacity made up of a few storage modules or even in certain cases only one module. Later on the storage capacity may be progressively extended up to its maximum value. But every time the storage capacity is modified by adding modules or by taking them away in the event of failure, it is necessary for the users of the systems to be warned and made aware of the change in order that they can employ the entire extent of available store, but within the exact limit of its capacity.
The display of the value of the capacity of the various stores employed in a system in order to continually inform the user of available capacity necessitates long and tedious manipulations over batteries of switches or wired connections for which the risks of errors are not negligible. These manipulations have to be undertaken at each instance of a new modification of the storage capacity. It is therefore the object of the present invention to make automatic the display of the storage capacity introduced as its real physical modifications proceed; to let this information be known directly to the organizations which are the users of the store; and to check the effective presence of all the storage modules when the modules are associated in order to form an indivisible fraction of the store in the case where a number of modules are associated in order to form an operational portion of storage.